Micromovements with migration of the tibial component are seen after both cemented and uncemented TKA during the first postoperative year. Subsequently most implants stabilize, while a minority migrate continuously beyond the first postoperative year (Ryd et al. 1995). The implants that continues to migrate are those with a high risk of later aseptic loosening. Several studies have evaluated the influence of different parameters such as mode of fixation (cemented/uncemented), surface coating e.g. hydroxyapatite, metal alloys, and design of the prostheses on the migration of the tibial component in primary TKA (Ryd 1986), but whether the use of a surface coating of trabecular metal (Titanium) will result in significant differences has not yet been evaluated.